Site-specific cleavage reaction catalyzed by leadzyme is enhanced by combined effect of lead and rare earth ions.

Lead-dependent ribozyme (leadzyme) is a ribozyme working with Pb2+. In this paper, we have investigated the combined effect of metal ions, especially rare earth ions, on the cleavage reaction by the leadzyme. As a result, it was observed that although only a rare earth ion or another divalent ion except Pb2+ did not play a role as the catalyst, the addition of a rare earth ion in the presence of Pb2+ increased significantly the yield of the cleavage reaction. The result suggests that the complex between the leadzyme and the substrate should have two classes of metal ion binding sites.